Bulk.find.updateOne()

On this page本页内容

Tip提示

Starting in version 3.2, MongoDB also provides the db.collection.bulkWrite() method for performing bulk write operations.从3.2版开始，MongoDB还提供了用于执行批量写入操作的db.collection.bulkWrite()方法。

Description描述

Bulk.find.updateOne(<update>)

Adds a single document update operation to a bulk operations list.将单个文档更新操作添加到批量操作列表。

Use the Bulk.find() method to specify the condition that determines which document to update. 使用Bulk.find()方法指定确定要更新哪个文档的条件。The Bulk.find.updateOne() method limits the update to a single document. Bulk.find.updateOne()方法将更新限制为单个文档。To update multiple documents, see Bulk.find.update().要更新多个文档，请参阅Bulk.find.update()。

Bulk.find.updateOne() accepts the following parameter:接受以下参数：

Parameter参数Type类型Description描述
updatedocument or pipeline

The modifications to apply. 要应用的修改。Can be one of the following:可以是以下之一：

A replacement document替换文件

Contains only field and value pairs.仅包含字段和值对。

See also Bulk.find.replaceOne().另请参见Bulk.find.replaceOne()。

Update document更新文档Contains only update operator expressions.仅包含更新运算符表达式。

Aggregation pipeline聚合管道

Starting in MongoDB 4.2从MongoDB 4.2开始

Contains only the following aggregation stages:仅包含以下聚合阶段：

For more information on the update modification parameter, see the db.collection.updateOne() reference page.有关更新修改参数的更多信息，请参阅db.collection.updateOne()参考页面。

The sum of the associated <query> document from the Bulk.find() and the update document must be less than or equal to the maximum BSON document size.Bulk.find()中关联的<query>文档和更新文档的总和必须小于或等于最大BSON文档大小。

Behavior行为

If the <update> document contains only update operator expressions, as in:如果<update>文档仅包含更新运算符表达式，如：

{
  $set: { status: "D" },
  $inc: { points: 2 }
}

Then, Bulk.find.updateOne() updates only the corresponding fields, status and points, in the document.然后，Bulk.find.updateOne()仅更新文档中相应的字段、status和points。

Example示例

The following example initializes a Bulk() operations builder for the items collection, and adds various updateOne() operations to the list of operations.下面的示例初始化items集合的Bulk()操作生成器，并将各种updateOne()操作添加到操作列表中。

var bulk = db.items.initializeUnorderedBulkOp();
bulk.find( { status: "D" } ).updateOne( { $set: { status: "I", points: "0" } } );
bulk.execute();

Update with Aggregation Pipeline使用聚合管道更新

Starting in version 4.2, update methods can accept an aggregation pipeline. 从4.2版开始，更新方法可以接受聚合管道。For example, the following uses:例如，以下使用：

  • the $set stage which can provide similar behavior to the $set update operator expression,$set阶段可以提供与$set更新运算符表达式类似的行为，
  • the aggregation variable NOW, which resolves to the current datetime and can provide similar behavior to a $currentDate update operator expression. 聚合变量NOW，它解析为当前日期时间，可以提供与$currentDate更新运算符表达式类似的行为。To access aggregation variables, prefix the variable with double dollar signs $$ and enclose in quotes.要访问聚合变量，请在变量前面加上双美元符号$$并用引号括起来。
var bulk = db.items.initializeUnorderedBulkOp();
bulk.find( {  status: "P" } ).updateOne(
   [
      { $set: { points: 0, lastModified: "$$NOW" } }
   ]
);
bulk.execute();
Tip提示
←  Bulk.find.replaceOne()Bulk.find.update() →